Cellulose-ether composition



Patented Sept. 8, 1925.

UNITED STATES PATENT OFFICE.

JOHN I. DOHOKUE, P nocnm'rim, NEW YORK, ASSIGROB 1'0 EASTIAH KODAK GOIIE'LIY, Oil noonrsm mew YORK, A COBPOBATIOII ,.OI mew YORK.

cuteness-mass. oourosn'rou.

Io Drawing.

To all whom it may concern:

Be it known that I, JOHN M. Doxonnn, a citizen of the United States of America, residing at Rochester, in the county of Mon- :roe and State of New York, have invented certain new and useful Improvements in solvent which will dissolve such large proportions of cellulose others that thick or viscous fiowable solutions ma beobtained for use in plastic and film making arts. Another object of my invention is to pgovide a cellulose ether solution which may manufactured into strong, flexible, transparent film on the machines and by the methods now in use. Other objects'will hereinafter appear.

In U. S. Patent No. 1,188,376, Lilienfeld, J une 20, 1916, there are disclosed a series of alkyl ethers of cellulose. Certain of these are practically insoluble in water, and my invention relates, but is not limited, to the 0 others having that pro rty. -While cellulose ethers form. thinsoliitions in the lower monohydroxy aliphatic alcohols or in butyrates of monohydroxy aliphatic alcohols containing from 3 to 5'carbon atoms inclusive,

3!! it has been fund that such single solvents by themselves do not dissolve a suflicient proportion of the ethers to make a com ition or do of the desired concentration and flowab e ualities, such as ma be used in 40 the manu iacture ofxphotograp ic film base by customa math s or in the plastic arts.

I have strong and useful solvent may be prepa by mixing one or more of the butyric' acid esters of the monohydroxy aliphatic alcohols containing from 3 to 5 carbon atoms inclusive with one or more of the lower monohydroxy aliphatic alcohols. B17 lower monoh droxy. aliphatic alcohols mean .60 those aving less than. 6 carbon atoms.

While the propyl butyrates, butyl butyratee and amyl preferred embodiment 'of my invention I amiscovered that an adequatgi utyrates are all useful, in the.

Application filed lebrlary 84, 1988. Serial Io; 681,064.

loy one of the amyl butyrates, say isoamyl lli%1l;at0."

ile the ingredients may be mixed in widely varyin proportions, it is noted, by way of examp e, that a particularly useful com ition can be prepared by mixing equa parts by weight of the butyrate and the alcohol, sayx isoamyl butyrate and methyl alcohol. In t e preferred form of my invention I dissolve 1 part by weight of the celluloseether, say water-insoluble ethyl cellulose in from 5 to 7 parts by weight of this solvent mixture. The ingredients by themselves are not sufliciently powerfulto make properly 'flowable dopes of this strength. Of course, the proportion of micro solvent or the proportion of the volatile ingredients may be increased to adapt the composition to the lacquering art, as will be understood by persons skilled therein.

,Other substances which impart additional suppleness, or incomhustibility, or other qiillalities, to the film may also be added to t e dope, such, for instance, as triphenyl or tricresyl phosphate, monochlornaphthalene,

'camphor, etc. The ingredients are of the ordinary commercial type and sufliciently purified for the process of film manufacture, so as-to give a dope yielding films having the proper relative freedom from color. The viscous-flowable dope above described can be used in connection with the usual film forming ap aratus without the necessity of ex nsive a terations in the latter.

n the formation of a film by the spread ing of such solution and the evaporation of its volatile ingredients a considerable amount of the butyrate remains behind, be-

cause of its relatively low volatility. It imparts useful lasti ing and other pro rties to the filih, which is normally flexible and transparent.

Havin thus described my invention, what -I .c aim as new and desire to secure by Letters Patent'is:

' 1.: A com tion of matter comprising pom '0 acid ester of acohol' having more .oelluloseether dissolved in'amixture of a butyric acid ester of a monohydroxy aliphatic alcohol having more than 2 and less than 6 carbon atoms, and a lower monohydroxy aliphatic alcohol;

3. A composition of matter comprising cellulose ether dissolved in a mixture of. methyl alcohol and one of the amyl butyrates.

4. A flowable composition comprising 1 part of cellulom ether dissolved in from 5 to 7 parts by weight of a mixture of a lower monohydroxy aliphatic alcohol and a. butyric acid ester of a monohydroxy aliphatic alcohol containing more than 2 and less than 6 carbon atoms.

5. A composition of matter comprising cellulose ether dissolved in a mixture of equal parts by weight of a lower monoh droxy aliphatic. alcohol and a butyric acid ester of a monohydroxy' aliphatic alcohol containing more than 2 and less than 6 carbon atoms.

6. A composition of matter comprising 2 arts by weight of water-insoluble ethyl celulose, 7 parts of isoamyl butyrate and 7 parts of methyl alcohol.

7. As an article of manufacture, a film comprising cellulose ether and a butyric acid ester of a monohydroxy aliphatic alcohol containing more than 2 and less than 6 carbon atoms.

8. As an article of manufacture a tough, flexible, trans arent film comprisingwaterinsoluble et yl cellulose and isoamyl butyrate.

Signed at Rochester, New York, this 16 day of February, 1923.. p

. JOHN M. DONOHUE. 

